JPH01138616A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH01138616A JPH01138616A JP62296529A JP29652987A JPH01138616A JP H01138616 A JPH01138616 A JP H01138616A JP 62296529 A JP62296529 A JP 62296529A JP 29652987 A JP29652987 A JP 29652987A JP H01138616 A JPH01138616 A JP H01138616A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- ferrite
- particles
- recording medium
- constitution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002245 particle Substances 0.000 claims abstract description 26
- 239000006247 magnetic powder Substances 0.000 claims abstract description 17
- 239000013078 crystal Substances 0.000 claims abstract description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 229920005989 resin Polymers 0.000 claims description 4
- 239000011347 resin Substances 0.000 claims description 4
- 239000011230 binding agent Substances 0.000 claims description 3
- 229910000859 α-Fe Inorganic materials 0.000 abstract description 22
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 abstract description 14
- 229910052596 spinel Inorganic materials 0.000 abstract description 8
- 239000011029 spinel Substances 0.000 abstract description 8
- 230000007613 environmental effect Effects 0.000 abstract description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 3
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052745 lead Inorganic materials 0.000 abstract description 2
- 229910021645 metal ion Inorganic materials 0.000 abstract description 2
- 238000000407 epitaxy Methods 0.000 abstract 1
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000003973 paint Substances 0.000 description 5
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 4
- 239000006249 magnetic particle Substances 0.000 description 4
- 229920000139 polyethylene terephthalate Polymers 0.000 description 4
- 239000005020 polyethylene terephthalate Substances 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- -1 polyethylene terephthalate Polymers 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 2
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 2
- 239000000020 Nitrocellulose Substances 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000005587 bubbling Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000012153 distilled water Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 229920001220 nitrocellulos Polymers 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 229920005749 polyurethane resin Polymers 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 description 1
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 description 1
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910000684 Cobalt-chrome Inorganic materials 0.000 description 1
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 description 1
- 239000005642 Oleic acid Substances 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 241001115903 Raphus cucullatus Species 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- WAIPAZQMEIHHTJ-UHFFFAOYSA-N [Cr].[Co] Chemical compound [Cr].[Co] WAIPAZQMEIHHTJ-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000003490 calendering Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000010952 cobalt-chrome Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000001493 electron microscopy Methods 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- DALUDRGQOYMVLD-UHFFFAOYSA-N iron manganese Chemical compound [Mn].[Fe] DALUDRGQOYMVLD-UHFFFAOYSA-N 0.000 description 1
- KFZAUHNPPZCSCR-UHFFFAOYSA-N iron zinc Chemical compound [Fe].[Zn] KFZAUHNPPZCSCR-UHFFFAOYSA-N 0.000 description 1
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 description 1
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- 229920001228 polyisocyanate Polymers 0.000 description 1
- 239000005056 polyisocyanate Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、オーディオテープ、ビデオテープ、フロッピ
ーディスク等のような記録媒体に関し、特に温度特性の
優れた塗布型の磁気記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to recording media such as audio tapes, video tapes, floppy disks, etc., and particularly to coated magnetic recording media with excellent temperature characteristics.
従来の技術
磁気記録媒体は通常ポリエチレンテレフタレートやポリ
イミドなどの非磁性担体とその表面上に設けられた磁性
粒子と結合バインダーを主成分とする磁性ＩΔで構成さ
れている。磁性層を構成する磁性粒子としては、従来ガ
ンマ酸化鉄（ｒ ＦｅｚＯ３）、酸化クロム（ＣｒＯ
□）、コバルト変成ガンマ酸化鉄（Ｃｏ−γ−Ｆｅｚ０
３） 、メタル粉などの針状のものが一般に用いられて
きた。最近、記録の高密度化が盛んに叫ばれる中、岩崎
らが提案した垂直記録方式が高密度記録が可能であるこ
とが示されている（例えば、岩崎俊−；垂直磁化を用い
た高密度磁気記録；日経エレクトロニクス １９７８年
８月７日号、Ｐ １００〜１１１）。上述のより高密度
記録の可能な磁気記録媒体としては、コバルト−クロム
などの蒸着合金薄膜やヘキサゴナルフェライｌ−などが
あり、特にヘキサゴナルフェライトの微粒子を磁性粒子
として用いた媒体は、塗布型の垂直磁気記録媒体として
期待されている。Conventional magnetic recording media are usually composed of a non-magnetic carrier such as polyethylene terephthalate or polyimide, and a magnetic IΔ mainly composed of magnetic particles and a binding binder provided on the surface of the carrier. Conventional magnetic particles constituting the magnetic layer include gamma iron oxide (rFezO3) and chromium oxide (CrO3).
□), cobalt-modified gamma iron oxide (Co-γ-Fez0
3) Needle-shaped materials such as metal powder have generally been used. Recently, there has been a lot of talk about increasing the density of recording, and it has been shown that the perpendicular recording method proposed by Iwasaki et al. is capable of high-density recording (for example, Shun Iwasaki; Magnetic recording; Nikkei Electronics August 7, 1978 issue, pages 100-111). The above-mentioned magnetic recording media capable of higher density recording include vapor-deposited alloy thin films such as cobalt-chromium and hexagonal ferrite.In particular, media using hexagonal ferrite fine particles as magnetic particles are coated type vertical It is expected to be used as a magnetic recording medium.
発明が解決しようとする問題点
近年、記録密度の向上とともに記録再生時における信頼
性向上がディジタル記録、高密度記録などにおいては強
く要望されている。記録再生時における信頼性向上のた
めには磁気記録媒体の磁気特性が環境変化、とりわけ温
度変化に対し安定であることが重要である。しかしなが
ら、前述のガンマ酸化鉄をはじめとする針状の磁性粒子
を用いた磁気記録媒体では、媒体の保磁力が温度上昇と
ともに減少する。一方、前述のへキサゴナルフェライト
を用いた磁気記録媒体では、媒体の保磁力は温度に対し
て正の係数をとる。このように磁気記録媒体の保磁力が
環境変化などによる温度上昇で変化すると、常温で磁気
ヘッドより発生する磁界により媒体に記録しても、保磁
力の変化によって、磁気ヘッドから発生する磁界ではも
はや媒体に最適な記録再生が行なえない問題点があった
。Problems to be Solved by the Invention In recent years, there has been a strong demand for improved recording density and improved reliability during recording and reproduction in digital recording, high-density recording, and the like. In order to improve reliability during recording and reproduction, it is important that the magnetic properties of a magnetic recording medium be stable against environmental changes, especially against temperature changes. However, in a magnetic recording medium using acicular magnetic particles such as the aforementioned gamma iron oxide, the coercive force of the medium decreases as the temperature rises. On the other hand, in the magnetic recording medium using the aforementioned hexagonal ferrite, the coercive force of the medium takes a positive coefficient with respect to temperature. If the coercive force of a magnetic recording medium changes due to temperature rise due to environmental changes, even if the magnetic field generated by the magnetic head is used to record on the medium at room temperature, due to the change in coercive force, the magnetic field generated by the magnetic head will no longer be able to handle the recording. There was a problem in that recording and playback that was optimal for the medium could not be performed.
問題点を解決するための手段
本発明は、前記問題点を解決するため、磁気記録媒体の
磁性層が保磁力の温度係数、かつ結晶構造の異なる２種
類の磁性粉粒子より構成され、しかもその２種類の磁性
粉粒子が互いに結晶学的にエピタキシーの関係にあるも
ので構成されるものである。Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides that the magnetic layer of a magnetic recording medium is composed of two types of magnetic powder particles having different temperature coefficients of coercive force and crystal structures. It is composed of two types of magnetic powder particles that are in a crystallographic epitaxial relationship with each other.
作用
本発明は、磁気記録媒体の磁性層が、保磁力の温度係数
、かつ結晶構造の異なる２種類の磁性粉粒子より構成さ
れ、しかもその２種類の磁性粉粒子は単に混合したもの
ではなく、互いに結晶学的にエピタキシーの関係にある
ものであり、保磁力の温度変化は存在する２種類の磁性
粉粒子の量により自由に制御可能となる。このようにし
て作製された磁気記録媒体は、環境変化に伴なう温度変
化に影響されることなく、安定に最適な記録再生が可能
となる。Effects of the present invention The magnetic layer of a magnetic recording medium is composed of two types of magnetic powder particles having different temperature coefficients of coercive force and crystal structures, and the two types of magnetic powder particles are not simply mixed; They are in a crystallographic epitaxial relationship with each other, and the temperature change in coercive force can be freely controlled by the amounts of the two types of magnetic powder particles present. The magnetic recording medium manufactured in this manner is not affected by temperature changes due to environmental changes, and enables stable and optimal recording and reproduction.
さらに単に特性の異なる２種類の磁性粉粒子を混合した
ものではないので、磁気記録媒体を作製するために重要
である磁性塗料の分散に対しても高分散が可能である利
点がある。また、混合物でない利点として、磁性粉粒子
の磁化の反転する磁界、すなわちスイッチング磁界の分
布が、温度変化に対して自由に制御でき、しかも安定で
あることがあげられる。Furthermore, since it is not simply a mixture of two types of magnetic powder particles with different characteristics, it has the advantage that high dispersion is possible for the dispersion of magnetic paint, which is important for producing magnetic recording media. Another advantage of not being a mixture is that the distribution of the magnetic field in which the magnetization of the magnetic powder particles is reversed, that is, the switching magnetic field, can be freely controlled against temperature changes and is stable.
実施例
以下本発明の一実施例について、図面を参照しながら説
明する。EXAMPLE An example of the present invention will be described below with reference to the drawings.
第１図は本発明の磁気記録媒体を構成する磁性層に含ま
れる磁性粉粒子の構成を模式化した図である。FIG. 1 is a diagram schematically showing the structure of magnetic powder particles contained in a magnetic layer constituting the magnetic recording medium of the present invention.
１はスピネル型フェライト、２はへキサゴナルフェライ
ト、２１はスピネル構造を有する層、２２はＢａ”、Ｆ
ｅ”、０２−を含む層を示す。すなわちマグネットブラ
ンバイト型構造のへキサゴナルフエライト２のＣ面上に
スピネル型フェライト１の特定結晶面（例えば、（１１
１） 、（００１）など）がエピタキシャル成長した構
成であり、結晶学にミスフィツトなく両者が配列するこ
とにより、保磁力の温度特性が改善され、しかも磁気ス
ピン軸がＣ軸に対して揃うことから他の磁気特性が損な
われることもない。ここで上記スピネル型フェライトと
しては、マグネタイト（Ｆｅ３０ｔ） 、ガンマ酸化鉄
（γ−ＦｅｚＯｘ） 、コバルト変成ガンマ酸化鉄（Ｃ
ｏ−γ−ＦｅＺＯｆｆ）、コバルトフェライト（Ｃｏｘ
Ｆｅｚ−ｘＯａ、ｘ ：任意）、鉛−鉄系フェライト（
ＰｄｙＦｅｚ−ｙＯａ、ｙ：任意）、亜鉛−鉄系フェラ
イト（ＺｎｓＦｅｚ−ｓＯｎ＋ｓ ：任意）、マンガン
−鉄系フェライト（ＭｎｔＦｅｚ−ｔｏｔ＋ ｔ：任意
）などであり、ヘキサゴナルフェライトとしては間・ｎ
ＦｅｚＯ：＋ （ただしＭはＢａｘ Ｓｒ、 Ｐｂ、
Ｃａからなる群より選ばれる一種あるいは２種以上共存
の金属元素で表わされる、ｎは５〜６）で構成されるマ
グネットブランバイト型構造を有するものであり、結晶
学的に０面（（ＯＯｌ）面）が発達した六角板状粒子で
ある。また、ヘキサゴナルフエライトは、上記構成にお
ける構成元素の一部のＦｅ元素を二価−四価金属イオン
ペア（ただし、二価イオンはＣ０２゛、Ｎｉ”、Ｃｕ”
、Ｚｎ”、四価イオンはＴｉ４＋、ｚｒ４＋、Ｍｏ”、
ｌ（ｆ’＋の任意の組み合わせである）と置換した構成
のフェライトである。1 is a spinel type ferrite, 2 is a hexagonal ferrite, 21 is a layer having a spinel structure, 22 is Ba'', F
e", 02-. That is, a specific crystal plane of spinel type ferrite 1 (for example, (11
1), (001), etc.) are epitaxially grown, and by arranging them without crystallographic misfit, the temperature characteristics of the coercive force are improved, and the magnetic spin axis is aligned with the C axis, which makes it possible to The magnetic properties of the material are not impaired. Here, the spinel type ferrites include magnetite (Fe30t), gamma iron oxide (γ-FezOx), and cobalt-modified gamma iron oxide (C
o-γ-FeZOff), cobalt ferrite (Cox
Fez-xOa, x: arbitrary), lead-iron ferrite (
PdyFez-yOa, y: arbitrary), zinc-iron ferrite (ZnsFez-sOn+s: arbitrary), manganese-iron ferrite (MntFez-tot+ t: arbitrary), etc.;
FezO: + (However, M is Bax Sr, Pb,
It has a magnetic brambite type structure composed of one or more coexisting metal elements selected from the group consisting of Ca, where n is 5 to 6, and crystallographically it has a 0-face ((OOl ) is a hexagonal plate-like particle with a developed surface. In addition, hexagonal ferrite is a divalent-tetravalent metal ion pair (however, divalent ions are C02゛, Ni'', Cu''
, Zn'', tetravalent ions are Ti4+, zr4+, Mo'',
This is a ferrite having a configuration in which l (which is an arbitrary combination of f'+) is replaced.
以下、本発明の一実施例の磁気記録媒体について説明す
る。A magnetic recording medium according to an embodiment of the present invention will be described below.
Ｃｕ”−Ｚｒ”イオンペアでＦｅの一部を置換したマグ
ネットブランバイト構造の六角板状バリウムフェライト
磁性粉粒子（保磁力Ｈｃ ８７０エルステツド、飽和磁
化Ｍｓ５０．９ ｅｍｕ／ｇ、平均粒径０．１１μｍ、
平均粒子厚み０．００７０ｐｍ、比表面積６６．０ｍ／
ｇ）を２２０ｇ採取し、あらかじめ窒素ガスでバブリン
グすることにより溶存酸素を除去した蒸留水３β中に窒
素ガスを通じつつ、反応容器中で懸濁させた。これに１
７０ｇの硫酸第１銖（ＦｅＳＯｎ ’ ７１１ｚＯ）を
蒸留水３１に完全に溶かした溶液を添加した。さらに２
規定の水酸化ナトリウム（Ｎａ０１１）１．５βを加え
、コロイド状懸濁液を作製し、これを含む反応容器を加
熱し、７０℃まで窒素ガスで懸濁液を撹拌しながら昇温
した。その後７０℃に温度を保ちつつ、バブリング用ガ
スを空気に切り換えた後、１０時間７０℃で撹拌しなが
ら反応を完了させた。得られた反応溶液を濾過し、濾過
により得た沈殿物を充分に水洗し、１３０℃のドライオ
ーブン内で乾燥することにより用いる磁性粉粒子を得た
。得られた磁性粉粒子は、Ｘ線解析によりマグネットブ
ランバイト相とスピネル相の２相であることが確認され
た。さらに電子顕微鏡観察及び電子線回折により上記の
２相は互いにエピタキシーの関係にあることが確認され
、複合−磁化したものであった。Hexagonal plate-shaped barium ferrite magnetic powder particles with a magnetic brambite structure in which a portion of Fe is replaced with Cu"-Zr" ion pairs (coercive force Hc 870 oersted, saturation magnetization Ms 50.9 emu/g, average particle size 0.11 μm,
Average particle thickness 0.0070pm, specific surface area 66.0m/
220g of g) was collected and suspended in a reaction vessel while passing nitrogen gas into distilled water 3β, which had previously removed dissolved oxygen by bubbling with nitrogen gas. 1 for this
A solution of 70 g of sulfuric acid No. 1 (FeSOn' 711zO) completely dissolved in distilled water 31 was added. 2 more
A colloidal suspension was prepared by adding 1.5β of the specified sodium hydroxide (Na011), and the reaction vessel containing this was heated, and the temperature was raised to 70° C. while stirring the suspension with nitrogen gas. Thereafter, while maintaining the temperature at 70°C, the bubbling gas was changed to air, and the reaction was completed while stirring at 70°C for 10 hours. The resulting reaction solution was filtered, and the precipitate obtained by the filtration was thoroughly washed with water and dried in a dry oven at 130° C. to obtain magnetic powder particles to be used. It was confirmed by X-ray analysis that the obtained magnetic powder particles had two phases: a magnetic brambite phase and a spinel phase. Furthermore, it was confirmed by electron microscopy and electron beam diffraction that the above two phases were in an epitaxial relationship with each other, and were compound-magnetized.
得られた磁性粉粒子（平均粒径０．１１μｍ、平均粒子
厚み０．００８５μｍ、飽和磁化５８．１ ｅｍｕ／ｇ
、保磁力６４０エルステツド、比表面積４８．９ｍ／ｇ
）を１００ｉｔ部に対して、ニトロセルロース樹脂１０
重量部、ポリウレタン樹脂１０Ｘｌｉ蛍部、オレイン酸
２重量部、カーボンブランク５重量部、α−アルミナ５
重量部、トルエン１２０重量部、メチルイソブチルケト
ン１２０重量部、シクロへキサノン８０重量部の混合物
をサンドミルを用いて１０時間混合分散して磁性塗料を
作製した。さらに上記磁性塗料にポリイソシアネート６
重量部添加し、混合分散した後０．５μｍペーパーフィ
ルターで磁性塗料を濾別した。The obtained magnetic powder particles (average particle size 0.11 μm, average particle thickness 0.0085 μm, saturation magnetization 58.1 emu/g
, coercive force 640 oersted, specific surface area 48.9 m/g
) to 100 parts of nitrocellulose resin
Parts by weight, 10Xli polyurethane resin, 2 parts by weight of oleic acid, 5 parts by weight of carbon blank, 5 parts by weight of α-alumina
A magnetic paint was prepared by mixing and dispersing a mixture of 120 parts by weight, 120 parts by weight of toluene, 120 parts by weight of methyl isobutyl ketone, and 80 parts by weight of cyclohexanone using a sand mill for 10 hours. Furthermore, polyisocyanate 6 is added to the above magnetic paint.
After adding parts by weight and mixing and dispersing, the magnetic paint was filtered off using a 0.5 μm paper filter.
濾別後の塗料をアプリケーターを用いて膜厚１５μｍの
ＰＥＴ （ポリエチレンテレフタレート）フィルム上に
塗布し乾燥させた。その後カレンダー処理を行ない、所
定の寸法幅にスリットし、測定用サンプルを作製した。The filtered paint was applied onto a 15 μm thick PET (polyethylene terephthalate) film using an applicator and dried. Thereafter, it was calendered and slit to a predetermined size and width to prepare a sample for measurement.
得られたサンプルの保磁力の温度変化はＶＳＭ （振動
試料型磁力計）を用いて調べた。その結果を図２に示す
。Temperature changes in the coercive force of the obtained sample were investigated using a VSM (vibrating sample magnetometer). The results are shown in FIG.
比較例として、市販のへキサゴナルフェライト磁性粉粒
子、ガンマ酸化鉄磁性粉粒子および両者の等モル比混合
粉をそれぞれ１００重量部として同様のサンプルを作製
し、同様の測定を行なった。As a comparative example, similar samples were prepared using 100 parts by weight of commercially available hexagonal ferrite magnetic powder particles, gamma iron oxide magnetic powder particles, and a mixture of the two in an equimolar ratio, and the same measurements were performed.
図２から明らかなように本発明の実施例における磁気記
録媒体は、保磁力の温度変化が環境温度に影古されずに
安定であることがわかる。比較例に示した混合物の場合
にも保磁力の温度変化は小さくなっているが、スイッチ
ング磁界分布が非常に変動しており、しかも媒体自身の
垂直方向の角形性が悪くなっており、高密度記録達成の
ための条件は満たされなかった。As is clear from FIG. 2, it can be seen that in the magnetic recording medium according to the example of the present invention, the temperature change in coercive force is not affected by the environmental temperature and is stable. In the case of the mixture shown in the comparative example, the change in coercive force with temperature is also small, but the switching magnetic field distribution fluctuates greatly, and the vertical squareness of the medium itself has deteriorated, resulting in a high density The conditions for achieving the record were not met.
以上述べたように本発明によれば、温度変化に対して安
定に最適な記録再生が可能となり、しかも高密度記録、
ディジタル記録可能な磁気記録媒体を提供することがで
きる。As described above, according to the present invention, it is possible to stably perform optimal recording and reproduction against temperature changes, and also to achieve high-density recording and
A digitally recordable magnetic recording medium can be provided.
樹脂バインダーとしてニトロセルロース樹脂とポリウレ
タン樹脂の２成分系で行なったが、塩化ビニル−酢酸ビ
ニル共重合体、塩化ビニル系などとの組み合わせを変え
て行なっても得られる媒体の特性には影響がなかった。Although we used a two-component system of nitrocellulose resin and polyurethane resin as the resin binder, changing the combination with vinyl chloride-vinyl acetate copolymer, vinyl chloride system, etc. does not affect the properties of the resulting medium. Ta.
また、溶剤の組み合わせもより好ましくは、トルエン、
メチルイソブチルケトン、シクロヘキサノンであるが、
特に限定する必要はない。さらに非磁性担体には実施例
においてポリエチレンテレフタレートを用いたが、ポリ
イミドフィルムや別のポリエステルフィルムに変えても
同様の結果が得られた。Further, the combination of solvents is more preferably toluene,
Methyl isobutyl ketone, cyclohexanone,
There is no need to be particularly limited. Furthermore, although polyethylene terephthalate was used as the nonmagnetic carrier in the examples, similar results were obtained even when polyimide film or another polyester film was used.
発明の効果
以上述べてきたように本発明によれば、保磁力の温度特
性に優れ、環境変化に対しても安定でかつ最適な記録再
生ができ、しかも他の磁気特性を損なうことなく高密度
記録可能ならしめることができ、信幀性向上が図れる。Effects of the Invention As described above, according to the present invention, the temperature characteristics of coercive force are excellent, stable and optimal recording and reproducing can be performed even against environmental changes, and high density recording can be achieved without impairing other magnetic properties. It can be made to be recordable, and reliability can be improved.
第１図は本発明の磁気記録媒体の磁性層を構成する磁性
粉粒子の構成を模式化した模式図、第２図は本発明の一
実施例および比較例の磁気記録媒体の保磁力の温度変化
を測定した結果を示したグラフである。
■・・・・・・スピネル型フェライト、２・・・・・・
ヘキサゴナルフェライト、２１・・・・・・スピネル構
造を有する層、２２−− Ｂａ ” ”、ｐ ｅ ：ｌ
＋、０２−を含む層。
／−一−スじ°ネル型フェラΔト
？−−−へ＋ワコ゛すルフェライト
ｚ１−−−ヌロネル１１隻＆山Ｖゐ１
２２−Ｍ”、Ｆ♂ θ２”−ｔきむ暮
第１図
どど
第２図
贋 境 滉Ｘ（’Ｋ）FIG. 1 is a schematic diagram illustrating the structure of magnetic powder particles constituting the magnetic layer of the magnetic recording medium of the present invention, and FIG. 2 is the temperature of coercive force of the magnetic recording media of an example of the present invention and a comparative example. It is a graph showing the results of measuring changes. ■・・・・・・ Spinel type ferrite, 2・・・・・・
Hexagonal ferrite, 21...layer having a spinel structure, 22--Ba"", p e :l
A layer containing +, 02-. /-One-step flannel type blowjob Δto? --- To + Wakosuru Ferrite Z1 --- Nuronel 11 & Yama V 1 22-M", F♂ θ2"-tKimukure 1st Figure Dodo 2nd Figure Fake Sakai 滉X ('K)
Claims (1)
成成分とする磁性層を設けてなる磁気記録媒体において
、保磁力の温度係数、かつ結晶構造の異なる２種類の組
成物より構成され、その２種類が互いに結晶学的にエピ
タキシーの関係にあることを特徴とする磁気記録媒体。A magnetic recording medium in which a magnetic layer mainly composed of magnetic powder particles and a resin binder is provided on a non-magnetic carrier, is composed of two types of compositions with different temperature coefficients of coercive force and crystal structures; A magnetic recording medium characterized in that two types of magnetic recording media are crystallographically in an epitaxial relationship with each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62296529A JPH01138616A (en) | 1987-11-25 | 1987-11-25 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62296529A JPH01138616A (en) | 1987-11-25 | 1987-11-25 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01138616A true JPH01138616A (en) | 1989-05-31 |
Family
ID=17834710
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62296529A Pending JPH01138616A (en) | 1987-11-25 | 1987-11-25 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01138616A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0416324A2 (en) * | 1989-09-05 | 1991-03-13 | Studer Revox Ag | Magnetic recording medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6111924A (en) * | 1984-06-27 | 1986-01-20 | Toshiba Corp | Magnetic recording medium |
| JPS63273211A (en) * | 1987-05-01 | 1988-11-10 | Dowa Mining Co Ltd | Magnetic recording medium |
| JPS63275103A (en) * | 1987-05-07 | 1988-11-11 | Matsushita Electric Ind Co Ltd | Magnetic recording medium |
-
1987
- 1987-11-25 JP JP62296529A patent/JPH01138616A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6111924A (en) * | 1984-06-27 | 1986-01-20 | Toshiba Corp | Magnetic recording medium |
| JPS63273211A (en) * | 1987-05-01 | 1988-11-10 | Dowa Mining Co Ltd | Magnetic recording medium |
| JPS63275103A (en) * | 1987-05-07 | 1988-11-11 | Matsushita Electric Ind Co Ltd | Magnetic recording medium |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0416324A2 (en) * | 1989-09-05 | 1991-03-13 | Studer Revox Ag | Magnetic recording medium |
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